Here’s what I received today from someone I don’t know:
“I have a favor to ask. I (sic) trying to get my book on the Amazon bestseller list. Today only, I am selling a digital Kindle copy of my book XXXXXXXXX for only 99¢. I am very proud of my book, I hope you can help me. Also, if you know others who would like a great business book, please forward this to them.”
This is what it’s come to: gaming the system. Ask strangers to promote your book, which you’re so “proud” of that you’re offering it for 99 cents and trying to falsely gain popularity.